This invention relates to a container. More particularly, but not exclusively, this invention relates to a container for receiving and storing a gas which is intended to be used as part of a pulse tube refrigerator (often known as a “cryocooler”). The container can be utilised in other applications outside the field of cryocoolers, for storing fluids.
The general function of a pulse tube cryocooler is well known to one skilled in the art, and generally includes the following features/components:                a) a piston and cylinder assembly for effecting cyclical movement of gas (e.g. Helium);        b) a regenerator for storing and recovering thermal energy of the gas moving cyclically in that direction as a result of the piston;        c) a pulse tube fluidly connected to the regenerator, acting as an insulator between the regenerator and the remainder of the cryocooler;        d) an inertance tube offering restriction and inertial effect to the cyclically moving gas, fluidly connected to the pulse tube; and        e) a container (often referred to as a “reservoir”) fluidly connected to the inertance tube, for storing a volume of gas. The combined effect of the inertance tube and the reservoir shifts the phase of the cyclical pressure relative to the mass flow.The function of the cryocooler is to provide cooling to a device, particularly cryogenic temperatures. The present invention has been devised to achieve temperatures lower than 80K.        
According to a first aspect of the present invention, we provide a container having a wall with a thickness defined by inner and outer surfaces, said inner surface defining an internal cavity for receiving fluid, the container having an opening through which fluid can enter/exit the container, said opening being connected to a fluid conduit at least a length of which extends through the wall in between the inner and outer surfaces thereof which exits through the inner surface to communicate with the internal cavity.
According to a second aspect of the present invention, we provide a pulse tube refrigerator/cryocooler system including a container according to the first aspect of the present invention.
Further features of the various aspects of the invention are set out in the claims attached hereto.